﻿using System;

/// <summary>
/// 把一个金额转为大写金额
/// </summary>
public class JeToDaXie
{
    /// <summary>
    /// 把一个金额转为大写金额
    /// </summary>
    /// <param name="d">小写金额</param>
    /// <returns>大写金额</returns>
    public string ToUpper(decimal d)
    {
        if (d == 0)
            return "零元";//整
        string je = d.ToString("####.00");
        if (je.Length > 15)
            return "";
        je = new String('0', 15 - je.Length) + je; //若小于15位长，前面补0   
        string stry = je.Substring(0, 4); //取得'亿'单元   
        string strw = je.Substring(4, 4); //取得'万'单元   
        string strg = je.Substring(8, 4); //取得'元'单元   
        string strf = je.Substring(13, 2); //取得小数部分   
        string str1 = "", str2 = "", str3 = "";
        str1 = this.GetUpper(stry, "亿"); //亿单元的大写   
        str2 = this.GetUpper(strw, "万"); //万单元的大写   
        str3 = this.GetUpper(strg, "元"); //元单元的大写   

        string str_y = "", str_w = "";
        if (je[3] == '0' || je[4] == '0') //亿和万之间是否有0   
            str_y = "零";
        if (je[7] == '0' || je[8] == '0') //万和元之间是否有0   
            str_w = "零";

        string ret = str1 + str_y + str2 + str_w + str3; //亿，万，元的三个大写合并   
        for (int i = 0; i < ret.Length; i++) //去掉前面的"零"   
        {
            if (ret[i] != '零')
            {
                ret = ret.Substring(i);
                break;
            }
        }
        for (int i = ret.Length - 1; i > -1; i--) //去掉最后的"零"   
        {
            if (ret[i] != '零')
            {
                ret = ret.Substring(0, i + 1);
                break;
            }
        }
        if (ret[ret.Length - 1] != '元') //若最后不位不是'元'，则加一个'元'字   
            ret = ret + "元";
        if (ret == "零零元") //若为零元，则去掉"元数"，结果只要小数部分   
            ret = "";
        if (strf == "00") //下面是小数部分的转换   
        {
            ret = ret + "";//整
        }
        else
        {
            string tmp = "";
            tmp = this.GetInt(strf[0]);
            if (tmp == "零")
                ret = ret + tmp;
            else
                ret = ret + tmp + "角";
            tmp = this.GetInt(strf[1]);
            if (tmp == "零")
                ret = ret + "";//整
            else
                ret = ret + tmp + "分";
        }
        if (ret[0] == '零')
        {
            ret = ret.Substring(1); //防止0.03转为"零叁分"，而直接转为"叁分"   
        }
        return ret; //完成，返回   

    }

    /// <summary>
    /// 把一个单元转为大写，如亿单元，万单元，个单元   
    /// </summary>
    /// <param name="str">这个单元的小写数字（4位长，若不足，则前面补零）</param>
    /// <param name="strDW">亿，万，元</param>
    /// <returns>转换结果</returns>
    private string GetUpper(string str, string strDW)
    {
        if (str == "0000")
            return "";
        string ret = "";
        string tmp1 = this.GetInt(str[0]);
        string tmp2 = this.GetInt(str[1]);
        string tmp3 = this.GetInt(str[2]);
        string tmp4 = this.GetInt(str[3]);
        if (tmp1 != "零")
        {
            ret = ret + tmp1 + "仟";
        }
        else
        {
            ret = ret + tmp1;
        }
        if (tmp2 != "零")
        {
            ret = ret + tmp2 + "佰";
        }
        else
        {
            if (tmp1 != "零") //保证若有两个零'00'，结果只有一个零，下同   
                ret = ret + tmp2;
        }
        if (tmp3 != "零")
        {
            ret = ret + tmp3 + "拾";
        }
        else
        {
            if (tmp2 != "零")
                ret = ret + tmp3;
        }
        if (tmp4 != "零")
        {
            ret = ret + tmp4;
        }
        if (ret[0] == '零') //若第一个字符是'零'，则去掉   
            ret = ret.Substring(1);
        if (ret[ret.Length - 1] == '零') //若最后一个字符是'零'，则去掉   
            ret = ret.Substring(0, ret.Length - 1);
        return ret + strDW; //加上本单元的单位   
    }

    /// <summary>
    /// 单个数字转为大写
    /// </summary>
    /// <param name="c">小写阿拉伯数字</param>
    /// <returns>大写数字</returns>
    private string GetInt(char c)
    {
        string str = "";
        switch (c)
        {
            case '0':
                str = "零";
                break;
            case '1':
                str = "壹";
                break;
            case '2':
                str = "贰";
                break;
            case '3':
                str = "叁";
                break;
            case '4':
                str = "肆";
                break;
            case '5':
                str = "伍";
                break;
            case '6':
                str = "陆";
                break;
            case '7':
                str = "柒";
                break;
            case '8':
                str = "拐";
                break;
            case '9':
                str = "玖";
                break;
        }
        return str;
    }
}